Mac to Mac communication

[prasadamjala]

Hi Experts,

We are using imx6qp controller in our project and also an ethernet switch (KSZ8795) which is having 1 mac(RGMII) and 4 phy ports.

The switch is connected to imx6qp in RGMII, i.e Mac to Mac and this swich is configurable with SPI and we are not using MDIO bus for configuration of switch.

My query is, in linux switch driver,

i. do i need to create PHY instance and connect to phy layer?

ii. do i need to create MDIO bus instance and register to bus? since i am using SPI to configure the switch.

Thanks,

Prasad

[aliismail]

Hi Prasad,

Were you able to complete this? I am also using the ksz8795. The spi-ksz8795 driver provided by microchip is up and running and I can communicate via SPI. I am stuck at the point where the Fast Ethernet Controller Driver (FEC) can attach to the ksz8795 driver. I am unable to ping the switch.

[aliismail]

Turns out we had a hardware issue! Our RX clock was connected incorrectly.

[suifengrumeng]

你好，请问你的KSZ8795已经通讯正常了吗？不知道能否指点一二，我现在也在调试这个芯片。我的SPI接口也通讯正常了，已经读出了设备ID。硬件连接采用的是RGMII接口和KSZ8795对接，SPI接口用来初始化KSZ8795，并没有使用到MDIO。我现在遇到的问题就是IMX6的fec_main.c并不能正常生成eth0的网卡设备。。。我对使用KSZ8795的理解是，现在采用这种方式连接，是否接下来要改写IMX6的fec_mian.c驱动，让他强制性认为外部有PHY，从而建立eth0设备，发出RGMII信号？？？

[zhangzhencai]

你好，我们最近在使用ksz8895和8795 没太大区别。你们现在用的内核版本是多少？我目前跟microchip技术沟通的情况是，如果你们只是连通不用vlan等其他功能的话，可以不用spi驱动。所以首先可以不用spi驱动，先在dtsi配置好，ping通设备。

[suifengrumeng]

恩，这种说法我在朋友那也听到了，他也是在microchip技术支持那边听说的。我现在是配置了SPI驱动，那我不用SPI驱动试下吧，QQ：541237941，可以沟通下，这里审批太慢了。。。

[zhangzhencai]

不好意思最近比较忙没有上论坛，好的 我加你qq。不过我们开发板改版要用ksz8895 和ksz8863，现在实物还没出来，提供的建议也是很有限。我觉得你们应该找一下nxp这边的支持。

[wqx0x]

兄弟，遇到了同样的问题，方便加下好友交流下吗。我的QQ是：164971887.   谢谢！

[zhangzhencai]

好的，我加你。

zhangzhencai@transengines.com

上海吉盛网络技术有限公司

Add:中国上海漕宝路51号2楼213室

Phone: 021-64088876-621

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[Pavel]

It looks like that this switch should be used in MAC-to-MAC connection.

Set "fixed-link" in .dts file for this switch.

Use additional SPI application for configuring of this switch.  

Have a great day,
Pavel Chubakov

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[eric_kang1]

Hi Pavel,

I'm using the KSZ8795 Ethernet Switch with RGMII.

But I couldn't find the reference schematics.

Could you share the reference RGMII Interface between i.MX6 and KSZ8795 RGMII if you have?

It's very helpful to me if I can have it.

Best Regards,

Eric.